Frequently Asked Questions

Question: Why don’t you publish horsepower values for your engines?

Answer: Most manufacturers’ horsepower values are meaningless, exaggerated, and/or done under conditions that make the engine look good on paper. Because there are so many factors that can influence horsepower figures, here is no real way to tell how they measured the horsepower…just try and get them to tell you! Also, when is the last time you have seen a 1.20 size 3D plane spinning a prop at 14,000 rpm with any form of thrust efficiency?

Taking published horsepower values and trying to translate them into something useful is very difficult. What modelers can instantly recognize for comparative purposes is propeller size, rpm and static thrust under real world conditions.

If you have 1:1, 1.5:1, or 2:1 thrust to weight ratio, you know pretty well what the performance will be with a given airplane/engine/prop combination. Remember, many static thrust claims are derived from some computer program. Some software is very accurate while some is very “generous”. Unlike most static thrust advertisements, ours is measured INSTALLED in a typical 1.20 size airplane restrained by a digital tension gauge. This is the only way to take into account the included of the wings and airframe

Question: What is different about Syssa Aircraft engines?

Answer: Almost all of our parts are actually made in the USA, in our facility, by our own highly automated and very accurate CNC machining centers. Any parts manufactured for us are done by an ISO company. Reed cages have 100% machined surfaces. Our cranks are forged steel and ground in one piece and our engine blocks, reed cages, and pistons and piston pins are machined completely out of wrought, high strength, specialty materials.

Our machined parts are of the highest quality, traceable, verifiable material from the USA and are manufactured to tight specifications/tolerances. They are QC’d at our facility by CNC probe and assembled here under tightly controlled conditions with specially developed fixtures and dedicated tools manufactured by us.

We use high quality, name brand bearings throughout. We also have parts in stock ready to ship out and knowledgeable people available by phone or email to help you out should you need it. Each engine block is serialized and logged; this gives us quick access to your engines history and age.

Question: How much will I actually save in fuel cost with a gas engine?

Answer: Throughout the world, glow fuel costs about $13-$30 a gallon so your savings, depending on the type, quality and nitro/oil content you use, will vary.  However, on average, if you pay $18 a gallon for glow fuel and make 4, 15 minute flights every other weekend in a year, you will save about $200 per year in fuel costs. Don’t forget about the cost of paper towels too! Gas is much cheaper, more available and on top of that, gassers typically consume fuel at half the rate of a comparable glow engine which will save you weight.

Question: How long is a typical flight time with the SAP-180HP™?

Answer: If your flying style is hardcore 3D, a 16 oz tank will easily allow you to fly for 15 minutes. Upon landing, you will have about 30% off a tank left depending on how well your engine is tuned.� We only recommend a 16 oz tank size as this for serious 3D to minimize the chance of the clunk “missing” fuel during very “snappy” maneuvers.

Question: How will I know if the SAP-180HP™ will be able to hover my plane?

Answer: If your plane weighs between 8 and 12 pounds, it will accelerate out of hover quite nicely. If it weighs between 13 and 16 pounds, pullout will be slower, and over 18 pounds will not have unlimited vertical. Everyone’s tastes differ, but generally, for “lively” 3D type performance, an SAP-180HP™ powered airplane should not weigh more than 13.5 pounds. Sport flying with the SAP-180HP™ will be fine with a plane up to 19 pounds. Don’t forget, this is still a 1.8 cubic inch (29cc) engine that weighs less than most 26cc engines and some 20cc engines!

Question: What prop is the best with this engine?

Answer: After trying countless propellers during testing, Xoar and Vess came out on top.  Their balance is excellent right out of the package. The efficiency is great and they are lightweight (and therefore spool up quickly) and very reasonably priced.  These are the only props we sell, and we chose to sell them exclusively because they worked so well on our engine during our flight testing.

Question: What other engines/products will you develop and sell?

Answer: Whenever we see a need in the RC Aircraft market! If you have a suggestion for an aftermarket product let us know! A very powerful, lightweight, boxer, twin cylinder (60cc), with parts based on our single, is currently under development along with a 175cc twin!

Question: What else do I have to do when installing a gas engine in my RC aircraft?

Answer: There are a few things you will have to do that are quite simple. Here is a quick guide of what you will have to/should do when going to gas:

  • Plan on about 85% less paper towel usage.
  • Do not use a metal rod in your throttle servo linkage.
  • The best throttle setup is to have a 2-56 ball link on the carb and a 2-56 Dubro™Kwik Link on the servo with a non-metallic rod in between (Sullivan GoldenRod™ works well.) You can connect the links to the plastic rod with two, short 2-56 threaded rods.  This allows for adjustability and smooth, reliable operation.
  • Try to keep your ignition battery a reasonable distance from your RX battery pack.
  • Unless you are using our Ultra IBEC, you should not “tap off of” or use your receiver battery pack to power your ignition.
  • Replace your glo fuel tank stopper with a gasoline rated stopper and replace all fuel lines with gas (correct grade of Tygon or Viton) fuel lines.
  • It is highly recommended to use (through your radio) a remote ignition shutoff system, such as one of our opto-isolated kill switches or Ultra IBE (Ignition Battery Eliminator Circuit) with built in opto-isolated kill switch.� This is in addition to being able to use your throttle servo to shut off your engine. Using a choke on a servo is also a good way to kill an engine remotely.
  • See our pre-flight checklist when flying any plane (gas or glow) for the first time!

Check back often for more FAQ’s!


Syssa Aircraft Performance
772 North Colony Road
Meriden, CT 06450

+01 (860) 538 – 2937
Hours: 9:00 am – 5:00 pm East Coast Time


“Your one stop shop for high performance gasoline engine, large scale aircraft needs!”

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